Methods and apparatus for generating electrical power have formed the basis of important energy systems for some time and have, accordingly, been the subject of relatively extensive study. Persons skilled in the arts of electrical power generation and use are familiar with a variety of ways in which electrical power is generated, transformed, converted and used.
Electrical power has been generated as a result of electrochemical effects, photovoltaic effects, and electrodynamic effects. Electrodynamics, in the most generally known form, deals with the flow of electricity in conductors. Using an analysis based on electrodynamics, the operating principle of a conventional generator is traditionally illustrated by a rotating loop of conductive material positioned so that the axis about which the loop rotates is perpendicular to the lines of flux of a magnetic field. Upon rotation, the conductor "cuts" the magnetic flux lines and the amount of magnetic flux passing through the plane of the rotating loop of wire varies periodically from zero to a maximum value, as the plane of the loop successively passes through positions parallel and perpendicular to the magnetic flux lines. Electrical current thus generated may be collected by means of slip rings (in the case of an alternating current generator) or by a commutator (in the case of a pulsating direct current).
It is known, in the construction and use of certain electrodynamic apparatus, to provide a mechanical prime mover such as a turbine for driving the electrodynamic devices, a relatively low power dynamoelectric apparatus for generating a "tickler" or "exciter" voltage, and a larger electrodynamic apparatus as a main generator. Such electrodynamic apparatus has been widely successful and has been the base upon which current usage of electrical powder has been built.
As mechanical designers appreciate, however, the rotational speeds at which such electrodynamic apparatus are capable of operating are somewhat limited, particularly where acceleration and deceleration are required or encountered. Thus, limitations upon the operation of such mechanically driven electrodynamic apparatus have been established by the mechanical limitations of the structures used.